If you did following with success:
git clone git://linuxtv.org/media_build.git
(alternately to get only the latest revision without history)
git clone --depth=1 git://linuxtv.org/media_build.git
cd media_build
./build
su
make install
thank you need to load the driver by
modprobe dvb-usb-it913x
If this suceeds you shoud get your /dev/dvb devices. (or see some logs in dmesg). Don't forget to copy the right fimrware file to the /lib/firmware folder!
It might require you to define udev rules for your device to get the driver loaded by hotplugging it.. but thats another story you will have to find this out yourself..